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When do prosocial actors experience positive versus negative psychological outcomes from helping others? In four studies and an internal meta‐analysis, we tested the hypothesis that autonomy shapes the psychological consequences of helping others. In Study 1, prosocial behaviour was associated with a robust pattern of negative well‐being outcomes (i.e., depression, anxiety, stress) for individuals low but not high in autonomy. In Studies 2–4, relative to reflecting on a neutral interpersonal experience, reflecting on an autonomous helping experience increased sadness and happiness, strengthened intentions to help in the future and raised support for social welfare. By contrast, reflecting on a controlled helping experience increased negative emotions and decreased positive emotions, but did not affect attitudes or behavioural intentions. Collectively, the findings indicate that autonomy (or lack thereof) shapes the emotional, motivational and attitudinal consequences of helping behaviour. [ABSTRACT FROM AUTHOR]

Mikecoxite, ideally (CHg4)OCl2, is the first mercury-oxide-chloride-carbide containing a C4– anion coordinated by four Hg atoms (a permercurated methane derivative) to be described as a mineral species. It was found at the McDermitt open-pit mine on the eastern margin of the McDermitt Caldera, Humboldt County, Nevada, U.S.A. It is monoclinic, space group P21/n, Z = 4; a = 10.164(5), b = 10.490(4), c = 6.547(3) Å, V 698.0(5) Å3. Chemical analysis by electron microprobe gave Hg 86.38, Cl 11.58, Br 0.46, C 1.81, sum = 100.23 wt%, and O was detected but the signal was too weak for quantitative chemical analysis. The empirical formula, calculated on the basis of Hg + Cl + Br = 6 apfu, is (C1.19Hg3.39)(Cl2.57Br0.05)Σ2.62, and the ideal formula based on the chemical analysis and the crystal structure is (CHg4)OCl2. The seven strongest lines in the X-ray powder diffraction pattern are [d (Å), I, (hkl)]: 2.884, 100, (230); 2.989, 81, (301, 301, 112, 112, 131, 131); 2.673, 79, (122, 122, 212, 212); 1.7443, 40, (060, 432, 432); 5.49, 34, (101, 101); 4.65, 32, (120); 2.300, 30, (312, 312). The Raman spectrum shows three bands at 638, 675, and 704 cm–1, well above the range characteristic of NHg4 stretching vibrations between 540 and 580 cm–1, that are assigned to CHg4 stretching vibrations. Mikecoxite forms intergrowths of bladed crystals up to 100 μm long that occur on granular quartz or in vugs associated with kleinite. It is black with a submetallic to metallic luster and strong specular reflections and does not fluoresce under short- or long-wave ultraviolet light. Neither cleavage nor parting were observed, and the calculated density is 8.58 g/cm3. In the crystal structure of mikecoxite, (C 4 − H g 4 2 +) groups link through O2– ions to form three-membered rings that polymerize into corrugated [CHg4OCl]+ layers with near-linear C4––Hg2+–O and C4––Hg2+–Cl linkages. The layers link in the third direction directly via weak Hg2+–O2– and Hg2+–Cl– bonds to adjacent layers and also indirectly via interlayer Cl–. A bond-valence parameter has been derived for (Hg2+–C4–) bonds: Ro = 2.073 Å, b = 0.37, which gives bond-valence sums at the C4– ions in accord with the valence-sum rule. The source of carbon for mikecoxite in the volcanic high-desert environment of the type locality seems to be methane, with the reaction catalyzed by microbiota through full mercuration of carbon atoms, beyond the first stage that produces the volatile and highly mobile methylmercury, [CH3Hg]+, a potent neurotoxin that accumulates in marine food chains. Both the mineral and the mineral name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA 2021-060). The mineral is named after Michael F. Cox (b. 1958), a founding member of the New Almaden Quicksilver County Park Association (NAQCPA) who was responsible for characterizing and remediating environmental mercury on-site and who recovered the rock containing the new mineral. [ABSTRACT FROM AUTHOR]

Kapundaite, ideally [(Na,Ca).sub.2][Fe.sup.3+.sub.4][(P[O.sub.4]).sub.4] [(OH).sub.3] x 5[H.sub.2]O, is a new mineral (IMA2009-047) from Toms phosphate quarry, Kapunda, South Australia, Australia. The new mineral occurs as cavernous aggregates of fibers up to several centimeters across, associated with leucophosphite, natrodufrenite, and meurigite-Na crystals and amorphous brown, black, and/or greenish coatings. Individual kapundaite crystals are very thin flattened fibers up to a few millimeters in length, but typically no more than a few micrometers in thickness. The main form observed is {100}; other forms in the [010] zone are present, but cannot be measured. Crystals of kapundaite are pale to golden yellow, transparent to translucent, have a yellow streak and silky luster, and are non-fluorescent. Mohs hardness is estimated to be about 3; no twinning or cleavage was observed. Kapundaite is biaxial (+), with indices of refraction [alpha] = 1.717(3), [beta] = 1.737(3), and [gamma] = 1.790(3). 2V could not be measured; [2V.sub.cale] is 64.7[degrees]. The optical orientation is Z = b, Y [approximately equal to] c with weak pleochroism: X= nearly colorless, Y= light brown, Z = pale brown; absorption: Y> Z > X. No dispersion was observed. The empirical chemical formula (mean of seven electron microprobe analyses) calculated on the basis of 24 O is ([Ca.sub.1.13][Na.sub.0.95])[summation]2.08[([Fe.sup.3+.sub.3.83] [Mn.sub.0.03][Al.sub.0.02][Mg.sub.0.01]).sub.[summation]3.89] [P.sub.3.92][O.sub.16]([OH).sub.3] x 5[H.sub.2.11]O. Kapundaite is triclinic, space group P[bar.1], a = 6.317(5), b - 7.698(6), c = 9.768(7) [Angstrom], [alpha] = 105.53[(1).sup.o], [beta] = 99.24[(2).sup.o], [gamma] = 90.09[(2).sub.o], V = 451.2(6) [[Angstrom].sup.3], and Z- 1. The five strongest lines in the powder X-ray diffraction pattern are [[d.sub.obs] in [Angstrom], (I) (hkl)]: 9.338 (100) (001 ), 2.753 (64) (2[bar.1]1), 5.173 (52) (011 ), 2.417 (48) ([bar.2][bar.1]-3, 202, 0[bar.1]4), and 3.828 (45)(0[bar.2]1). The crystal structure was solved from single-crystal X-ray diffraction data using synchrotron radiation and refined to [R.sub.1] = 0.1382 on the basis of 816 unique reflections with [F.sub.o] > 4[sigma]F. The structure of kapundaite is based on a unique corrugated octahedral-tetrahedral sheet, which is composed of two types of chains parallel to a. Kapundaite is structurally related to melonjosephite. The mineral is named for the nearest town to the quarry. Keywords: Kapundaite, new mineral, phosphate, Toms phosphate quarry, crystal structure, octahedral-tetrahedral sheet, melonjosephite DOI: 10.2138/am.2010.3466

The open-branched tetrahedral chain of sapphirine-group minerals contains tetrahedra with 1-3 bridging O atoms ([Q.sup.1], [Q.sup.2], and [Q.sup.3]). The topology implies that short-range order (SRO) driven by bonding enthalpies forces some long-range order (LRO). This is an ideal system to investigate the interplay between SRO, LRO, and configurational entropy. Results are presented of Monte Carlo simulations of ordering patterns involving Be, Al, and Si on the branched chain. The 'Loewenstein's Rule' enthalpy term favoring AlOSi links is insufficient to obtain the experimental LRO occupancies. Additional site-dependent potentials repelling Si from [Q.sup.1] and [Q.sup.2] and driving asymmetry between the two [Q.sup.3] sites are needed. All enthalpy terms are close to 2 RT in magnitude, so the observed LRO cannot be regarded as arising dominantly from Si-avoidance. A 'Markov Braid' method is presented of calculating configurational entropies for the simulations. The substantial SRO present is shown to reduce [S.sub.config] by only 17-18%. Khmaralite is related to sapphirine but contains ca. 1.5 Be per 12 tetrahedra and shows different LRO of {Be, Al, Si}. The minority cation Be is concentrated in [Q.sup.3] sites. If the exchange enthalpy [DELTA][H.sub.AlSi] = -2 RT, then [DELTA][H.sub.BeAl] and [DELTA][H.sub.BeSi] must be -6.5 to -7.5 RT to reproduce the observed mean Q for Be, Al, and Si. Khmaralite has a doubled chain period relative to sapphirine. This superstructure enables the formation of tetrahedral Be-octahedral [Fe.sup.2+] clusters in the structure. A small number of site-specific potentials allows the LRO of the khmaralite chain to be reproduced, but 'Be-avoidance' remains by far the dominant interaction. Site occupancies were extrapolated to Be-rich compositions. More than 1.7 Be atoms per 12 tetrahedra is predicted to drive Be into new sites and create unfavorable BeOBe links, and to drive Si from [Q.sup.3] into the [Q.sup.1] sites. This is likely to be why the related mineral welshite, which can incorporate higher Be contents, has a quite different Be ordering pattern and symmetry. Keywords: Branched tetrahedral chain, khmaralite, sapphirine, welshite, aluminum, beryllium, silicon, aluminum avoidance, beryllium avoidance, configurational entropy, long-range order, Markov braid, short-range order, silicon avoidance

Apparent superlattice reflections obtained in electron diffraction patterns of modulated calcite and dolomite have been ascribed to local domains of various different metastable Ca-Mg ordering schemes that are not known as macroscopic phases. We show that the type 'c' reflections in diffraction patterns of supposed superstructures can in fact be produced by superposition of diffraction from the host crystal and that from domains that are in an orientation related to the host by twinning on (104). From details of the additional reflections present, we deduce that the carbonate anions are orientationally disordered in the twin nanodomains, which have the R[bar.3]m space group of high-temperature disordered calcite. This twinning can explain the diffraction ascribed to type '[gamma]'/'micro'/'v' superstructures, and resolves controversies over the occurrence of these purportedly different superstructures. The relationships between composition, orientational order of the carbonates, molar volume and known macroscopic structures, and the possibility of interracial strain reduction by static disorder in the twin domain, are discussed. We stress the importance of checking for presence of twinned nanodomains using microdiffraction before attributing an apparent superstructure modulation to local cation ordering. High-resolution imaging may not be diagnostic, since overlap of small domains and host matrix can give Moire patterns that resemble superlattice fringes. Keywords: Calcite, dolomite, twinning, superstructures, electron diffraction

From the first discovery in 1959 until the present, the abandoned Clear Creek mine has yielded an exceptional suite of rare and unusual mercury-bearing minerals unequaled in the world. Among [...]

A study was conducted on Al-Si ordering in natural and synthetic sapphirine crystals using magic-angle sample-spinning and high-resolution nuclear magnetic resonance. The Si environment was found to be similar for all samples of sapphirine crystals while the Al spectrum showed only one maximum peak. Intense peaks in the range of -73.1 were also observed in the Si spectra. Further observations showed that resolution decreased as the Si content increased, indicating a concomitant disorder increase in natural samples.